FOR MARINATING THE BEEF: 1 pound flank steak(sliced against the grain into 1/4-inch/6mm thick slices) 2 teaspoons neutral oil (such as vegetable, canola, or avocado oil) 2 teaspoons Shaoxing wine (or dry cooking sherry, optional) 1 teaspoon soy sauce 1 tablespoon cornstarch 1 tablespoon water 1/4 teaspoon baking soda FOR THE SAUCE: 1/4 cup light brown sugar 3/4 cup hot water (or hot low sodium chicken or beef stock) 1/4 cup soy sauce 1 teaspoon dark soy sauce (optional) FOR COATING…